Propeller mechanism



1943. w. J. Bl ANcHARD ETAL 2,307,102

PROPELLER MECHAN I SM Filed June 16, 1959 4 sheets-sheet 1 ,Jan. 5, 1943.

w. J. BLANCHARD EI'AL PROPELLER MECHANISM Filed June 16, 1959 4 Sheets- Sheet 2 M v 8 V w: m8 5 mm A mw N RV m: s s 9 E n m W\ ww 98 E 8 Q mfi NQ Q NQM a 8 mm 2 mm WN 99 NM :5

Jan. 5, 1943. w. J. BLANCHARD ET AL PROPELLER MECHANISM Filed June 16, 1959 4 Sheets-Sheet 5 J. BLANCHARD ETAL 2,307,102

PROPELLER MECHANISM Jan. 5, 1943.

4 Sheets-Sheet 4 Filed June 16, 1939 IIIIA'II Patented Jan. 5, 1943 V PROPELLER MECHANISM Werner J. Blanchard and Charles S. J. MacNeil,

Dayton, Ohio, assignors to The Winters National Bank and Trust Company, Dayton, Ohio, a national banking corporation, as trustee Application June 16, 1939, Serial No. 279,531

29 Claims. (Cl. 170-163) This invention relates to adjustable blade propellers and more particularly to regulating devices therefor.

It is a principal object of the invention to provide a self-contained regulator unit for controllingthe setting of an adjustable propeller blade which is simple in construction and operation and which provides for accurate regulation and control of the pitch angle of the blade and over its speed of rotation.

It is a further object to provide a regulator assembly of this character having its own fluid pressure medium of proper predetermined characteristics as best suited for the purpose and which may be recirculated entirely apart from the engine lubricating system.

It is also an object to provide a regulator for a hydraulically adjustable propeller in which the fluid pressure system is entirely contained within mechanism which rotates with the propeller, requiring no fluid pressure connection to the engine or other stationary part.

It is also an object to provide a regulator device of this character in which a member rotatable with the blades and arranged to be acted upon by substantial centrifugal force is made to control directly the application of hydraulic pressure to secure accurate setting of the blades and regulation of the engine speeds to accurate values.

It is a further object to provide a fluid circulating system for developing the hydraulic pressure for controlling the setting of the blades which is operative to establish and thereafter only as required to maintain the desired fluid pressure conditions, thereby avoiding unnecessary working and generation of heat.

It is a still further object to provide a single regulator assembly of this character having controls for effecting change of the pitch setting of the blades over a wide range, such as from a position of negative pitch to a position where the blades are fully feathered.

Other objects and advantages will be apparent from the following description, the accompanying drawings, and the appended claims.

In the drawings- Fig. 1 is a view in perspective of a propeller mounted upon a driveshaft and showing the general relation of the regulator invention of the present device with respect thereto;

Fig. 2 is a vertical sectional'view through the axis of the regulator device constructed in accordance with the present invention;

Fig. 3 is a vertical sectional view at right angles to Fig. 2 and on the line 33 of Fig. 2;

Fig. 4 is likewise a vertical sectional view in the same plane as Fig. 3 but spaced axially therefrom and along the line 44 of Fig. 2;

Fig. 5 is a vertical sectional view through Fig. 2 on the line 5-5;

Fig. 6 is a sectional view through the pump chamber on the line 66 of Fig. 3;

Fig. 7 is a sectional view through the pump valves on the line l| of Fig. 3;

Fig. 8 is a detail sectional view on the line 8-8 of Fig. 4;

Fig. 9 is a detail sectional view on the line 9-9 of Fig. 4;

Fig. 10 is a detail sectional view on the line |lll0 of Fig. 4;

Fig. 11 is a detail sectional view of the pump on the line ll-H of Fig. 6;

Fig. 12 is a detail. sectional view of the regulator valve on the line 12-42 of Fig. 2;

Fig. 13 is a view looking toward the regulator device in the direction of the arrows iii-I3 on Fig. 3 with the enclosing housing or casing thereof removed;

Fig. 14 is a detail elevational view looking toward the regulating device with the casing removed on the line I l-l4 of Fig. 2;

Fig. 15 is a detail sectional view on the line i5-I5 of Fig. 2;

Fig. 16 is a detail plan view looking toward the adjustable regulator ring which is shown in Fig. 15;

Fig. 17 is a horizontal sectional view through one of the blade sockets along line I'l-ll of Fig. 2 showing the fluid pressure conduits leading into the hub for supply of control fluid thereto.

In order to provide for adjustment of the setting of the blades in a hydraulically adjustable propeller, suitable means are provided for effecting change in the pitch angle of the blades under the action of selectively applied and controlled hydraulic pressure. In copending application Serial No. 279,530 filed concurrently herewith, an adjustable blade propeller is shown in which selectively and positively applied hydraulic pressure is utilized to efiect both pitch-increasing and pitch-decreasing change in the blade'setting, the blades being adjustable over the usual flight range into a feathered position, and also into a negative pitch position to provide a negative thrust for purposes of landing, maneuvering, and the like. The present invention provides a regulator assembly arranged to develop and supply to the hub and blade structure separately controlled sources of hydraulic pressure for positively actuating the blade in each direction,

' throughout its range of adjustment to secure predetermined desired setting of the blades. This fluid pressure application is so regulated over the normal flight range as to provide for maintaining substantially constant speed of the propeller within such range as selected either manually or in accordance with instrument control, that speed being subject to change as required. And by reason of the particular construction and arrangement of the invention as hereinafter described, a highly accurate and definite speed condition is provided so that for example where a plurality of aircraft propellers are driven by separate engines, the regulating means provides for maintaining accprate conditions of setting of the blades such as to establish accurate speed control and to avoid objectionable noise and vibration from beats produced by the engines.

The invention is likewise applicable for similarly controlling a propeller which utilizes positively applied hydraulic pressure for actuating the blades only in one direction, either for pitch-increasing or pitch-decreasing purposes, the blades being returned in the opposite direction of movement under the action of centrifugal force, resilient means, or the like.

Referring to the drawings which disclose a preferred embodiment of the invention the propeller blades Ill are shown as adjustably and rotatably mounted within hub II the hub being provided with blade sockets corresponding to the number of blades, three being shown herein. The hub is driven from driveshaft i2 projecting outwardly from the engine casing I3, the axis of rotation of the driveshaft being shown at l4. The regulator of the present invention is indicated generally at l5. and comprises a structure located in relation to the hub so as to be rotatable therewith, avoiding the necessity for establishing fluid-tight Joints for the supply of pressure operating fluid between a stationary and a rotatable part of the mechanism. Preferably as shown the regulator assembly is located immediately in front of the motor casing and adjacent to and rearwardly of propeller hub Ii.

The hub II has a sleeve portion l6 formed integrally therewith which is provided with spline teeth I! for engaging a similar spline upon the driveshaft I2, to provide for rotation of the hub therewith. A wedging ring I8 and locking ring l9 retain the hub in proper driving relation upon the shaft l2.

Bolted to the motor casing I3 by means of bolts 22 is a stationary plate 23 extending radially inwardly and provided with a series of bolts 24 for supporting an annular ring member 25 thereupon in stationary relation with respect to the motor casing. The ring 25 is formed integrally with a flange 26 which extends radially outwardly 6 thereof and has a turned-over end portion 21 which is provided with a succession of lobes around its periphery to function as a cam. Preferably the cam 21 has two high points alternating with two low points uniformly arranged around its periphery.

Seated within a recess in the sleeve portion l6 of the hub and extending radially outward therefrom is an annular member 30 which serves as a support for the valve and pump casings and associated operating mechanism. Member 30 is held in place upon the sleeve It by means of a locking ring 3| spaced inwardly from ring 25 with sufficient clearance to permit of rotation of ring 3| and member 30 along with hub ll, out of contact with stationary ring 25.

Member 30 extends radially outward and receives a cover plate 33 in fluid sealed relation upon its outer periphery, the cover plate having an inwardly extending web portion 34 supported upon and sealed with respect to the ring 25. The cover 33 is bolted to member 30 by means of a series of bolts 35 such that it can be removed to provide access to the interior of the regulator housing. When in position the cover thus forms a completely enclosed chamber or reservoir for the reception of the hydraulic actuating fluid. and provides a fluid-tight connection preventing escape of fluid from within the chamber. For this purpose a sealing member 31 is adapted to engage the flange 34 and ring 25, being retained in sealing position by means of contractile spring 38 and cover plate 39. Likewise to prevent escape of fluid from within the housing, a sealing member 40 is provided between the inner end portion of member 30 and ring 25, being similarly retained in place by means of spring 4| and cover plate 42, held in place by bolts 43.

The pump structure and control mechanism is located within the space enclosed between the cover 33 and member 30 so that it is sealed against passage of fluid therefrom and continuously subjected to and operative in the reservoir of fluid pressure medium received therein which serves to lubricate and transfer heat therefrom. Upon rotation of the housing, fluid contained therein will move radially outwardly toward the inner wall of cover 33, which thus forms a reservoir for the fluid. the quantity thereof preferably being such that it practically fills the reservoir with only a relatively small clearance volume.

The inlet for picking up fluid from the reservoir comprises a funnel-shaped member having a screening device 46 over the opening and extending radially outwardly toward the inner wall of the reservoir. It approaches but is spaced somewhat therefrom to avoid picking up any sludge or other deposit from the fluid, but is relatively close so that it will be assured of receiving a supply of fluid. Passing through the funnel, the fluid enters through port 41 the valve chamber 48 of a cut-oil? valve 49. Valve 49 stands radially of the housing so that the body thereof is subjected to outward centrifugal force in the direction to open the valve, variable with the speed of rotation. A compression spring 50 acts in the same direction as centrifugal force, to urge the valve toward open position with a constant force. The valve has a stem 5| the end of which is acted upon by fluid pressure from a pressure chamber 52 in communication with the pressure side of the pump. Pressure so applied acts to urge the valve toward closed position so that upon the development of a pressure on the delivery side of the pump of the proper value, that pressure will be made effective upon the valve stem, to cause the closing of the shut-oil. valve and the consequent termination of the supply of fluid into the pump chamber. A safety by-pass 53 is likewise provided through the valve chamber, which is uncovered by the valve stem only after the inlet port has been substantially closed off, this by-pass providing for relief in the event of the operation of either of the pumps for the period immediately following the closing-off of the inlet Ports.

Likewise in order to avoid possible damage to the parts of the mechanism should the pump valve fail to close upon attaining the desired pressure, a safety disk is provided in the valve cap 56 .over the pressure chamber 52 which is adapted to rupture upon the attaining of a pressure in excess of the maximum fluid pressure desired; andprior to the rupture of any of the operating parts of the mechanism.

The passage 51 leads from the control side of the shut-off valve directly into the pump valve" chamber 60. Preferably the pumps and valve means therefor are duplicated, to provide more uniform conditions of operation and of developed pressure, and for this purpose a double passage 51 leads from the inlet valve chamber 48 to two and associated valve means is similar to the other,

only one such structure will be described in detail. Each pump comprises a cylindricalsleeve member 64 mounted fixedly in the pump chamber 6! and slidably receiving the pump piston 65 therein. The piston and cylinder are relativelyelongated axially to provide a substantial bearing area and to maintain a fluid-tight seal in the absence of any packing material under the pressure conditions which are developed within the pump. It will be noted that the pump piston is mounted so that its movement is not responsive to centrifugal action, the centrifugal action merely resulting in a side thrust upon the cylinder which is adequately provided for by the large bearing area. A compression spring 66 serves to move the piston outwardly of the cylinder, and the piston is guided for longitudinal reciprocating movement by means of a cross guide arm 61 of rectangular cross section which travels in a correspondingly-shaped guideway 68 formed in the chamber 6!. Piston 65 is provided with a recess at its outer end and roller 10 is supported therein on a bearing member H carried by cross arm 61. The roller 10 serves as a cam follower and has rolling bearing engagement with the face of cam 21 to cause corresponding movement of the pump piston 65.

As previously described, cam 2] preferably has a plurality of lobes, which are followed by the piston and the roller as the assembly rotates about the fixed cam to cause reciprocating movement of the pump piston, to a closed position under the action of the cam and then outwardly under the action of spring 66. In the arrangement shown the two pump cylinders are preferand this passage leads directly into the pump valve chamber 50. The valve structure'within the chamber 60 comprises an annular member 76- positioned within the chamber and forming a suction chamber H at the radially outer end of chamberfifl communicating directly with the suction inlet passage 57. Member 16 is provided with a series of apertures l8 therein providing for toward seating position with a force correspondas to the speed plus the force exerted by spring 'i'ln'nular member a: defines the chamber is. and is also provided at its end with a series of apertures l3 leading into the discharge chamber 84 formed in valve chamber 60 toward the a sure, which causes it to flow back into chamber the passage of the fluid from chamber ll into the centrally located pump chamber 3-9, when the suction valve 89 is raised from its seat. Valve' centrifugal force so that it is continuously urgedeffective within the chamber 52 and upon the radially inner end thereof and defined by annular member 85. A discharge valve 86 provides for the closing of! of the ports 83 and is urged toward closing position by means of spring 8'! and is likewise acted upon in the same direction by centrifugal force.

The operation of the pump and valve mechanism is as follows: Upon movement of the piston G5 to expand the pump chamber under the action of spring 66, a reduced pressure is made effective within chamber 19 closing valve 85 and opening valve 80. As a result of reduced pressure fluid is introduced from the reservoir through inlet 65, past the shut-off valve 49, through passage 51, into the suction chamber 11 through the passage 18, and into the chamber 1-9 from which it flows directly into the pump cylinder. Upon the return stroke of the pump, the piston is cammed positively in the opposite direction, thereby subjecting the fluid within its cylinder to pres- 19 under pressure. This causes the closing of suction valve 80-, and the opening of discharge valve 86 to supply the fluid under pressure to the discharge chamber 84.

The discharge chamber 84 leads directly into a pressure conduit 90 which is preferably formed as an integral unit comprising a tube 9| of copper, steel or the like cast integrally in a housing comprising the annular member 30. As shown this conduit is arranged in circular form, providing the pressure conduit 90 extending in continuous arcuate manner around the member 30 and having communication with boththe pump and valve assemblies, so that pump discharges directly thereinto. a

The intake chamber and shut-off valve device is provided with a passage having direct communication with conduit '90, to provide for making the fluid pressure developed by the pumps valve stem 5| of the shut-off valve as previously described. Thus upon operation the pumps will jointly produce-a pressure within conduit 90 which is returned through passage 95 to effect actuation of the shut-oil valve 49 upon the pressure valve stem 51 moves radially inwardly against the action of spring 50 and of centrifugal force to a closed position to substantially close oif the suction inlet opening 41. Thereafter, although the pump piston 65 continues to be actuated in response to rotation, it merely produces cavitation in the suction passage without drawing in fluid, and does'not continue to do work and to build up an excessive and unnecessary pressure. As a result-therefore unnecessary working and hea.t

ing of the body of fluid with resultant necessity.

for. dissipation of the heat are substantially avoided.

It will be further noted that as the shut-off valve 59 is responsive to centrifugal force as well as to a constant spring pressure, the pressure required to effect closing thereof will vary with the speed of rotation. Inasmuch as the forces of friction and the like which resist a change in position of the propeller blades are subject to increase with greater speeds of rotation, it will usually be found that greater operating forces are required with higher rotative speeds; and by the construction described such greater operating pressures are automatically provided for in accordance with this invention.

In order to secure control over the position of the blades of the propeller and hence to' maintain a predetermined selected speed condition of the propeller. means are provided for regulating the blade setting automatically in accordance with the speed of operation. For this purpose the member 30 is provided with an enlarged portion I which serves to house the regulator valve assembly. Mounted in thesleeve IN is the regulator valve body I02 which as shown stands substantially radially so that it is itself directly subject to centrifugal force. As shown it comprises a cylindrical body portion having two spaced valve faces, I03 and I04. A passage I05 leads through sleeve MI and into the part I00 where it communicates upon opposite sides with the two pressure conduits 90 so that the maintained fluid pressure is supplied directly to the central portion of the valve I02, between the two valve faces thereof. Being of equal projected area, the pressure between the two faces is balanced and the valve body moves freely irrespective thereof.

A passage I06 is formed through sleeve IOI in line with valve face I03, the width of the valve face being slightly greater than the width of the passage so that when properly centered the valve face will entirely close off the passage. Similarly passage I01 is related to and controlled by valve face I04. Passage I06 communicates directly with intermediate conduits H0 and passage I01 similarly communicates with inner conduits II I which are arranged in suitable manner, preferably concentrically with conduit 90, so that the entire assembly comprising the three conduits can be constructed and cast as an integral unit.

Conduits H0 and III are arranged for selective communication with the blade actuating mechanism so that upon application of fluid pressure to one of said conduits, that fluid pressure is communicated to and made effective to actuate the blade adjusting mechanism of each of the blade sockets of a multi-blade propeller in such manner as to increase the blade pitch; and similarly application of fluid pressure to the other of said conduits is made effective to control the pitch of each of the blades in the opposite direction. This communication is estab-- lished by means of conduits H3 and III extending through the rear face of each blade socket II and communicating respectively with outlets H3 and III formed in conduits H0 and III. The corresponding outlets of each group are located at the same radial distance from axis It, the radial distance of the two groups being difierent. These conduits H3 and Ill thus are in direct communication with conduits H0 and III, respectively, and lead directly into the interior of each blade socket where suitable means are provided for effecting an increase in the pitch angle of the blade upon fluid pressure being supplied to conduits H0, H4 and for effecting decrease of the pitch angle upon pressure being supplied to conduits III, H3. In the event that it is desired to supply pressure fluid to eflect actuation of the blade in only one direction and to utilize other means such as centrifugal force, or springs to cause the opposite blade movement,

only a single such pressure conduit need be utilized.

Means are likewise provided for venting the fluid from one conduit during the supplying of fluid to the other and for this purpose the sleeve MI is open at its radially inner end as shown in Fig. 2 so that fluid returning through passage III and entering through ports I01 can pass directly into the reservoir. At its radially outer end, the sleeve I M is provided with a number of discharge, ports I I2 so that fluid returning through conduit H0 and passage I06 can likewise be freely discharged into the reservoir.

For purposes of adjustment and operating control, valve body I 02 is provided with a cylindrical portion Hi to which is connected a yoke member I I 6 upon opposite sides thereof and having a threaded socket III formed therein. A lever arm H8 is threadedly and adjustably engaged in the socket. Likewise extending outwardly from and fixedly attached to the sleeve MI is a pair of guideways I20. Slidably mounted upon guideways I20 is a friction clamp I2I having an adjustable bolt I22 therein for varying the frictional engagement therewith, and formed at its outer Side with a concave roller I23 adapted to engage the arm II8.

Formed integrally with arm H8 is a yoke arm I24 having hooks I25 at either end thereof for engagement with tension springs I26. These springs are relatively elongated and such as to 0 develop substantial force, having their opposite ends fastened to a convenient point within the casing, such as the hooks I21 formed integrally upon pump chamber GI. As shown these springs lie outwardly of the brackets I28 fastened to projections I20 formed upon annular member 30, contacting the brackets in positions of rest substantially as shown in Fig. 3. Under the action of centrifugal force, these two springs assume a somewhat arcuate position, but because of the consequent less direct line of action of the spring force, continue to urge the yokeshaped arm I24 and arm II8 radially inwardly and with a maintained force which is substantially constant at varying speeds or in which the variations are insignificant practically so far as the regulating action is concerned.

Roller I23 thus forms a fulcrum, lever IIO pivoting about its center, and through connection of the lever with the regulator valve body I02 acts to urge the valve body radially inward against the action of centrifugal force which acts oppositely thereon. The force with which the valve body is urged inwardly remains practically the same for any fixed setting of the roller I23 regardless of the speed of rotation as above described. However upon the shifting of roller I23axially along pin I20, the effective lever arm of the spring force on yoke I24 is altered, a movement for example of roller I23 to the right as shown in Fig. 2 providing for the spring force being exerted with a greater lever arm. The lever arm through which this force is applied to the valve body is also increased by the same length but because it is already longer than the arm through which the spring force is applied. its length increases less in proportion and consequently there is a net increase in the inward force applied to the valve body, hence balancing a greater centrifugal force effective upon the valve body. The opposite condition occurs upon movement of the roller to the left.

vIn the operation of the regulator valve, with a fixed positioning of the adjustable roller I23,

corresponding to a predetermined engine speed condition which it is desired to maintain, a decrease in speed will result in a reduction of centrifugal force eflective upon the valve body I02 so that with the constantly acting force of the regulator springs I20, the valve body will be caused to move radially inwardly. As a result thereof, valve face I04 will uncover passage I01 and the source of pressure fluid supplied through passage I05 will be communicated through'port I01 into pressure conduit III. This supply of pressure fluid is delivered through the passages II3 which lead into the several blade sockets and to the blade adjusting mechanism contained therein, being applied in such direction as to effect a change in the setting of the blades to decrease the pitch thereof so that with a lesser angle of pitch, the speed will tend to increase and be restored to its predetermined desired condition. Simultanously with the supply of pressure fluid into conduit III, valve face I03 has moved inwardly to uncover the passage I06, thereby permitting fluid to exhaust from conduit I I0 and from the opposite side of the actuating piston, back into the reservoir through passages II2.

As the propeller increases its speed by reason of the reduced pitch angle of the blades, the added centrifugal force is effective immediately and directly upon the valve body I02 so as to cause the same to move radially outwardly to such position as to cut off further communication from the pressure passage through the passage I01, the valve moving outwardly to such point that its outward centrifugal force reaches a condition of balance with the inwardly applied spring force. If this condition corresponds with the predetermined desired speed condition as determined by the position of roller I23, the valve body occupies such position that communication with both conduits H0 and III is prevented. The valve body thusconstitutes its own followup device, and because it is directly affected by centrifugal force itself, without the interposition of additional moving parts involving frictional losses, it is highly sensitive and quickly responsive to even quite small changes in speeds of operation. It will be further noted that the valve is rotated at the same speed as the propeller itself, and furthermore is positioned at a substantial radial distance from the axis of rotation so that centrifugal force effective thereon is quite substantial, and differences occurring from even small changes in speeds of rotation are highly effective to bring about the regulating action as described above. This is highly desirable in connection with multi-motored planes, in order to provide for operation of each of the propellers at such speeds as to avoid setting up objectionable vibrations, and to avoid the objectionable effects of beats from the operation of the two motors at speeds only a few R. P. M. apart. With the arrangement of the present invention a highly critical condition of regulation is provided, such that these operating characteristics in multimotored planes are rendered unobjectionable, and such that a high degree of accuracy of regulation is provided.

position of the blade by increasing the pitch angle thereof, with simultaneous venting of the fluid from conduit III. This produces a reduction in the speed of operation, which is similarly responded to by the valve body to terminate the correcting application of fluid pressure, and to restore the system to its condition of stable equilibrium.

The construction of the regulator valve body as thus described likewise provides a control which is responsive to the rate of change of speed, inasmuch as a rapidly falling speed condition for instance will result in a greater degree of movement of the valve body I02 inwardly, to thereby open the port I01 more widely, to thereby supply pressure fluid at a greater rate from the source of pressure supply. The same is true of the reverse condition, the sensitive regulator body thus providing an accurate and sensitive control for such operating conditions as encountered.

The present construction provides a regulator construction which combines the features of sta bility through the normal working range, and at a sufficiently low idling speed, and a high degree of sensitivity particularly in the normal working range of speeds and blade angles. As will be evident, the movement of regulator valve body I02 results in a change in its radial position and hence in the centrifugal force effective thereon. To counterbalance this condition, the center of roller I23 is offset inwardly a slight distance from the line joining the point of connection to the valve body and the effective point of application of the spring force to lever H8. Hence as the valve body moves outwardly, lever arm I I8 pivots about roller I23 and thereby its effective length is slightly increased, the arm in effect rolling about the center of the roller. Although actually a small value, it produces a counterbalancing action and provides for securing the desired stability and sensitivity, the sensitivity with the construction disclosed actually increasing with increase in speed in the operating range so that a very satisfactory condition in this respect is provided.

As described above, shifting the position of the roller I23 effects a change in the force of the regulator springeifective upon the valve body, and thereby causes the regulator to seek and to become balanced at a different speed of rotation. Thi is desirable in order to provide for selection of the desired speed, either manually, or under the action of a control instrument. For the purpose of enabling selection of the desired speed for the operation of the regulating device, means are provided for shifting the position of roller I23 and predetermining or adjusting its position at any time during operation. As shown this means comprises a manual control member I30, pivotally mounted on a bearing member I3I carried by one of the engine bolt 22, and having suitable connection at I32 for a control wire, lever, or the like. The end of lever I30 within the cover plate 23 is formed with segmental gear teeth I33 which mesh with teeth I34 of a segmental pinion I35 carried by a rotatable shaft I36. Shaft I36 is rotatably mounted within the ring 25, and extends axially beyond the flange 26 thereof, being provided with an outwardly projecting arm I31 adjacent the inner surface of the flange 26. Arm I31 projects through a bracket I38 formed integrally with a ring I 39 rotatably received upon the outer face of ring 25. A snap ring I40 fitting within ring 25 serves to prevent axial movement of the ring I39 with respect to the ring 25 while providing for relative circular movement taking place therebetween. Tongue I38 is provided with a slot I4I therein through which arm I31 projects, the slot being either straight or curved to provide for securing the proper increments of rotation of ring I39 in response to the actuation of lever I30 and the movement of the arm I31.

A cam ring I44 having a central peripheral groove I45 therein is mounted upon the outer face of ring I38, and carries a fixed pin I46 which extends radially inwardly thereof through a spirally arranged slot I41 formed in the ring I39, and into an axially arranged slot I48 formed in ring 25. As a result of this construction, .and upon rotation of ring I39 about its axis, spiral slot I41 travels with respect to pin I 46 and because the cam ring I44 is held against rotational movement by the engagement of pin I46 in axial slot I40, the entire pin and cam ring is caused to move axially under the guidance of pin I45, in slot I48. A plurality of such pin and slot means are provided around the periphery of the ring in order to develop a balanced driving force and to avoid binding of the ring, any tendency toward binding being further reduced as a result of the full lubrication of thepart exposed within the reservoir, and .by reason of the relative rotational movement simultaneously taking place between the cam ring and ring I39. Accordingly movement of lever I30 is made effective to produce a predetermined axial shifting in the position of cam ring I44, the particular relationship depending upon the contour of the cooperating arm and slot I as previously described.

In order to transmit this movement of the cam block into a corresponding movement of the roller I23, diametrically opposite cam followers I50 carried by levers II are engaged within the groove I45. Levers I5I are pivotally mounted upon fulcrum arms I52 carried by the brackets I28, and are adapted to be rocked thereon in response to movement of cam ring I44. The levers at their opposite ends are preferably connected together by a cross strut I53 and have outwardly extending parts I54 each formed with a clevis engaging lugs I55 formed upon the bracket I56 to which the friction clamp I2I is attached. A shown in Fig. 13, movement of the cam ring I44 axially results in pivoting of lever arms I5I and the consequent movement of the friction block I2I axially over the supporting rod I20. Thus in response to adjustment of the lever I30 either manually or by instrument control, the fulcrum roller I23 is made to change its position, causing a change in the force with which the regulator spring acts upon the regulator valve body, to in turn result in regulating the speed of operation of the propeller blades to a value corresponding to the selected speed desired, equilibrium being established at the desired new speed condition in the manner as previously described.

Fbr example when the control lever I30 is actuated to such position as to cause the fulcrum roller I23 to approach the point of application of the regulator springs, the moment of application of that spring force is reduced, thus causing the valve body to move outwardly and to effect the application of fluid pressure in such direction as to effect an increase in the setting of the blade angle. The speed thus slows down and the centrifugal force effective upon the valve body to balance the regulator spring force 'is likewise reduced. 'I'hisls provided for automatically by the regulator action as above described, the blade angle being progressively increased with a correspondingly reduced speed of rotation of the blades the closer the fulcrum point of the roller I23 approaches the point of application of the regulator springs. In the position where roller I23 has been moved into substantial alignment with the point of application of the spring force, there is no longer any effective moment of that force to move the valve inward, and the regulator valve body is thus caused to move outward to increase the pitch of the blades to the ultimate position in which they are feathered. Preferably the roller is made to actually move slightly beyond the point of application of the spring force so that there is a positive force actvin r 10 hold the valve body in the outer position and assurance thus provided that the blades will be actuated to their fully feathered position and maintained there.

In order to restore the blades to an operative position after being fully feathered and stationary, the propeller may be cranked sufliciently to develop a control pressure in the system, thereafter allowing the propeller to windmill if in flight. If not in flight, the blades may be mechanically restored to operative position, or a separate control pressure may be utilized through suitable connections as desired.

On the other hand, as the fulcrum roller I23 moves to the right as shown in Fig. 2, a greater force is applied from the regulator spring to the valve body causing it to move inwardly to such position as to effect the application of pressure to decrease the pitch of the blade. The blade then speeds up producing a greater centrifugal force upon the valve body so that the regulator provides for reducing the setting of the blade angle as the, fulcrum roller is progressively moved further in this direction.

Since the valve body stands within and displaces fluid contained in the reservoir, such fluid exerts a pressure effect upon the valve body tending to oppose the action of centrifugal force thereupon. As the level of the fluid is reduced by depletion, such opposing force is lessened with the result that the valve body will move outwardly and reach equilibrium at a slower actual speed of rotation than that for which the control I30 is set, thereby indicating to the pilot the loss of or reduction in the quantity of fluid in the reservoir.

As illustrated in Fig. 5, the control member I30 is adjustable over its normal working range to increase the pitch angle setting of the blades, the flnal position in this direction being the fully feathered position of the blades. When the control lever is adjusted in the opposite direction, the pitch angle of the blades is decreased below the normal working settings, into a zero pitch position, and ultimately into a position of negative pitch. If the blades occupy a position of zero pitch or such low pitch that no substantial load is placed upon the engine, and this condition is continued for even a relatively brief period of time, an excessive speed condition may develop in the engine except as means are provided for overcoming such tendency. In the device of the present invention the /period required for the blades to shift to a negative pitch position which would impose substantial load upon the motor is quite brief, for example of the order of only a few seconds following actuation of the control lever from aposition within the working range to a negative pitch position. Ordinarily this period is of such short duration that an excessive or dangerous speed condition of the motor does not develop.

velopment of the speed of the motor in excess of a predetermined maximum, such means for example being a centrifugally responsive throttle control. Thus the control lever may be safely actuated to the full negative pitch position inwhich the force of the regulator spring is made operable to securely retain the valve body in its inner position, the regulating action of the valve body not being desired during operation under negative pitch positions.

In order to avoid possibility of the regulator coming into action while the blades are in a position of negative pitch, the lever I52 is provided with a pair of hook members I58 whichin the negative pitch position thereof are caused to engage over the equalizer yoke I24 to positively However if desired suitable speed limiting means may be incorporated to prevent de-.

I with said propeller hub, a relatively stationary hold the same in the maximum raised position where the regulator is no longer responsive to centrifugal force. When it is desired to restore the blades to a condition of positive pitch, actuation of the control lever in the opposite direction first eflects withdrawal of the hooks I58, then moves roller I23 to reduce the lever arm to such point that the centrifugal force on the valve body moves it outwardly, causing supply of pressure fluid in the direction to reduce the negative pitch. The means above described provides for safely controlling the engine speed in the transition zone of zero-blade pitch.

The invention thus provides a highly accurate and stable though sensitive regulator device for maintaining control over the blade positionings and over the speed of operation. In use a desired speed condition is maintained with such accuracy that objectionable beats from multi engines are avoided. Being self-contained the system is less subject to failure and the fluid itself is that best adapted forv the purpose. And the adjustable control provides for securing regulation of the operative condition at a selected range not only in the normal operative range, but to a negative pitch position and to a feathered position as well, utilizing only a single control member. I I

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

1. A propeller control mechanism for a hydraulically adjustable constant speed propeller of the character described which comprises a housing rotatable with the propeller shaft, a reservoir in said housing for receiving a quantity of pressure actuating fluid, pump means within said housing communicating with said reservoir and operable upon rotation of said propeller for establishing a supply of fluid under pressure, a regulator valve member within said housing and member projecting into said housing, means for establishing a fluid seal between said housing and said stationary member providing a reservoir within said housing for receiving a quantity of fluid pressure medium, pump means within said housing having operative engagement with said stationary member and actuated upon relative rotational movement between said stationary member and said housing to provide a source .of said fluid under pressure, means within said .housing for limiting the action of said pump means after the establishment of a predetermined pressure to thereafter maintain a supply of said fluid under said condition of predetermined pressure available for use as a source of pressure operating fluid, means responsive to the speed of rotation of said propeller for selectively controlling the application of said pressure operating fluid at a predetermined speed of operation, and

, providing a sealed reservoir within said housing for receiving a. quantity of fluid pressure medium,

pump means within said housing and actuated movable in a substantially radial direction for selectively controlling said supply'of pressure fluid in response to increase or decrease of the upon relative rotational movement between said stationary member and said housing to provide a source of said fluid under pressure, means for limiting the action of said pump means after the establishment of a. predetermined pressure to thereafter maintain a supply of said fluid under said condition of predetermined pressure, means for effecting variation in the pressure established and maintained in accordance with the speed of operation of the propeller to provide increased pressure upon higher speeds of rotation, and a regulator valve member for selectively controlling the application of said pressure fluid to said hub in accordance with the speed of rotation of said hub.

4. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the'pitch of the blades, comprising a housing rotatable with the propeller shaft, a relatively stationary member projecting into said housing, means for establishing a fluid seal between said housing and said stationary member providing a sealed reservoir within said housing for receiving a quantity of fluid pressure medium, pump means within said housing and having an inlet in communication with said reservoir toward the outer periphery thereof, means for actuating said pump means upon relative rotational movement between said stationary member and said housing to provide a source of said fluid under pressure, valve means responsive to the development of a predetermined pressure by said pump means to automatically limit the supplying of pressure by said pump means while a predetermined pressure exists, and .a regulator valve member within said housing responsive to the speed of rotation for selectively controlling the application of said pressure to said fluid actuated means to effect change of pitch of the propeller blades.

5. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the pitch of the blades, comprising a housing rotatable with the propeller hub, a relatively stationary member projecting into said housing, means for establishing a fluid seal between said housing and said stationary member providing a reservoir within said housing for receiving a quantity of fluid pressure medium, pump means within said housing and having an inlet in communication with said housing, means in operative engagement with said stationary member for actuating said pump means upon relative rotational movement between said stationary member and said housing to provide a source of said fluid under pressure, rotatable valve means mounted to be responsive to centrifugal force and movable under the action thereof for cutting off the supply of fluid to said pump means, inlet valve means for controlling the supply of fluid to said pump means, means for supplying pressure from the delivery side of said pump means to said inlet valve to oppose the action of centrifugal force and to provide for the closing thereof upon the attaining of a predetermined pressure condition by said pump means varying with the speed of operation, and speed responsive means for selectively controlling the application of said fluid pressure to said fluid actuated means to adjust the pitch of said blades.

6. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the pitch of the blades comprising a housing rotatable with the propeller shaft forming a sealed self contained reservoir for operating fluid, a plurality of pump means within said housing, a common discharge passage into which all of said pump means discharge, a relatively stationary member extending into said housing means for effecting positive operative engagement of said pump means with said stationary member for actuating said pump means in timed relation to each other to provide for successive discharge thereof into said common discharge passage to effect creation of a sustained fluid pressure therein, inlet valve means for controlling the supply of fluid to said pump means, a connection from said common discharge passage to said inlet valve means, and means associated with said inlet valve means for causing closure thereof upon the attaining of a predetermined pressure condition within said discharge passage, and a regulator valve within said housing and directly responsive to centrifugal force for selectively controlling the application of said fluid pressure to said fluid actuated means to effect change of pitch of the blades.

7. A propeller control mechanism of the character described for use with an-adjustabie blade propeller having fluid actuated means for effecting change in the pitch of the blades comprising a housing adapted to be rotated with the propeller hub, fluid sealing means for sealing said housing and providing a self contained reservoir for receiving avquantity of pressure actuating lluid, a stationary member extending into said housing, means outside said housing for securing said stationary member against rotation during operation, pump means rotatable with said housing and having operative engagement with said stationary member to effect actuation thereof upon rotation, a suction inlet positioned adjacent the outer periphery of said reservoir for receiving said pressure fluid and supplying the same to said pump means, means within said housing and responsive to a predetermined speed of operation of said propeller for controlling the application of said pressure fluid to said fluid actuated means to effect a change in the pitch angle of the propeller blades, means for discharging said fluid following the utilization thereof in such pitch changing operation back into said reservoir and means operable continuously from outside said hub and interconnected with said speed responsive means for varying the predetermined speed to which said means responds.

8. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the pitch of the blades comprising a source of pressure fluid, a regulator valve body mounted for rotation with the propeller hub and being itself directly responsive to centrifugal force and subject to generally radial movement in response thereto, means for opposing said movement with a substantially constant force, a control passage communicating with said hub and adapted to receive said pressure fluid for transmission to said fluid actuated means to cause a change in the pitch angle setting of the propeller blades, means cc titrolled by the position of said regulator valve body for effecting predetermined application of said source of fluid pressure to said control passage in accordance with the speed of operation of said hub, and means operable externally of said hub and mechanically connected with said opposing means for changing the effective force with which said valve body is opposed to predetermine the regulation thereof to a desired different speed condition.

9. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the pitch of the blades comprising a sealed housing rotatable with said propeller and adapted to contain a quantity of operating fluid, means within said housing for subjecting said fluid to pressure, a regulator valve body mounted within said housing for rotation movable radially directly in response to centrifugal force, means for supplying the pressure fluid under the control of said regulator valve body to said fluid actuated means to cause change in the pitch angle setting of the propeller blades, resilient means acting with a substantially constant force irrespective of the speed of said propeller for opposing the action of centrifugal force on said valve body and providing for the maintaining of a predetermined desired speed condition of said propeller by said regulator device, means for applying the force of said resilient means to said valve body, and means for modifying the action of said applying means to compensate for changes in the centrifugal force acting on said valve body as a result of movement thereof.

10. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the pitch of the blades comprising a source of fluid pressure, a regulator valve body mounted for rotation with said propeller and directly responsive to centrifugal force, means for supplying the pressure fluid under the control of said regulator valve body to said fluid actuated means to cause change in the pitch angle setting of the propeller blades, resilient means acting with a substantially constant force irrespective of the speed of said propeller for opposl5 ing the action of centrifugal force on said valve body with a predetermined regulated force, a lever for applying the force of said opposing means to be effective upon said valve body, and an adjustable control operable from the exterior of said rotating propeller for varying the efiective moment arm of said lever.

11. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for efiect- 5 ing change in the pitch of the blades comprising a source of fluid pressure, a regulator valve body mounted for rotation with said propeller and directly responsive to centrifugal force, means 'for 'supplying the pressure fluid under the control of said regulator valve body to said fluid actuated means to cause change in the pitch angle setting of the propeller blades, resilient means acting with a substantially constant force irrespective of the speed of said propeller for oppos ing the action of centrifugal force on said valve body with a predetermined regulated force, a lever for applying the force of said opposing means to be effective upon said valve body, and non-rotating means operable from outside said,4 0 propeller control mechanism for shifting the ful-' crum point of said lever to vary the effective moment arm thereof and to secure regulation of the speed of the propeller to a predetermined desired range.

12. A propeller control mechanism of the character described for use with an adjustable blade propeller having fluid actuated means for effecting change in the pitch of the blades comprising a source of fluid pressure, a regulator valve body 5 mounted for rotation with said propeller and di rectly responsive to centrifugal force, means for supplying the pressure fluid under the control of said regulator valve body to said fluid actuated means to cause change in the pitch angle setting of the propeller blades, resilient means acting with a substantially constant force irrespective of the speed of said propeller for opposing the applying the force of said opposing means to be" action of centrifugal force on said valve body with a predetermined regulated'force, a lever for effective upon said valve body, and means operative upon outward radial movement of said valve body under the action of centrifugalforce for increasing the effective moment arm of the lever to compensate therefor and maintain stability of operation.

I 13. A self contained propeller control mechanism of the character described for a hydraulically adjustable propeller comprising an annularv sealed reservoir rotatable with said propeller hub for receiving a quantity of pressure actuating fluid and having its inner periphery entirely open and unobstructed, pump means within and communicating with said reservoir for receiving a 75 supply of pressure fluid and subjecting the same to pressure, an arcuate pressure tube extending around and generally conforming to said reservoir and having communication with the pressure side of said pump means, a regulator valve body likewise within said reservoir and mounted to be responsive to the speed of rotation of said propeller, and a pressure supply conduit controlled by said regulator valve body, said pressure supply conduit being arcuate and concentrically arranged with respect to said pressure tube, and connections from said pressure conduit to the propeller hub for effecting supply of pressure fluid thereto.

14. A propeller control mechanism of the character described for a propeller comprising a substantially annular shaped member mounted adjacent and rotatable with the propeller hub and having its inner periphery entirely open and unobstructed and being receivable over the propeller shaft, a pump chamber, a -pump valve chamber, and a regulator valve means all rotatable with said hub, an outer housing sealed with respect to said annular member completely enclosing said chambers and said valve means and forming an annular shaped reservoir for receiving a quantity of fluid pressure actuating medium, an inlet for said pump chamber communicating with said annular reservoir adjacent the outer periphery thereof, tubes within said reservoir connecting said chambers to provide for supply of said pressure fluid therebetween, connections leading from said tubes through said annular member into communication with the propeller hub to supply said fluid actuating medium thereto as controlled by said regulator valve body, and actuating means in said hub for effecting adjustment of the pitch of the blades upon the application of said fluid pressure medium thereto.

15. A self-contained propeller control mechanism for a constant speed hydraulically adjustabl propeller having fluid actuated means for effecting change in the pitch of its blades and adapted to maintain a high degree of accuracy of speed regulation comprising a housing mounted upon a shouldered portion of said propeller hub and rotatable therewith, a stationary member projecting into said housing, fluid seal means for maintaining a fluid sealed connection between said housing and said stationary member, said housing providing a reservoir for receiving a quantity of fluid pressure actuating medium, pump means within said housing and rotatably carried by said hub, means cooperating with said pump means and said stationary member to effect a pumping operation and the development ,of a source of fluid pressure upon rotation of said hub, means to limit the action ofsaid pumping means to provide for building up and maintaining a predetermined desired condition of pressure and thereafter terminating the action of said pumping means, a regulator valve body within said housing and rotatable with said hub and directly responsiveto centrifugal force, means for opposing the centrifugal force effective on said valve body with a predetermined force, means for supplying pressure fluid from said pump means to said valve body, a control passage adapted to receive fluid pressure under control of said valve body for direct supply to said propeller hub to secure a change in the blade angle setting of said propeller blade, and means operable from outside said housing for causing a. change in the force with which said opposing means opposes the action of centrifugal force on said valve body to thereby cause the same. to be inequilibrium at a different predetermined speed condition, thereby maintaining a predetermined speed condition.

16. A propeller control mechanism for an hydraulically adjustable propeller of the character described comprising a propeller hub, a source of fluid pressure, a regulator valve rotatable with said hub and directly responsive to centrifugal force for controlling the application of said pressure, means for applying a predetermined force to said valve body to eflect regulation thereof, means for varying and predetermining the force so applied including a lever system through which said force is transmitted to the valve body, a member rotatable with said hub for varying the effective length of the lever arm, a non-rotating adjustable control member, and connections between said control member and said rotating member for effecting operation of the latter and adjustment of the lever arm in response to adjustment of said control member.

17. A propeller control mechanism for an hydraulically adjustable propeller of the character described comprising a propeller hub, a source of fluid pressure, a regulator valve rotatable with said hub and responsive to centrifugal force for controlling the application of said fluid pressure, means for applying a predetermined force to said regulator valve in opposition to said centrifugal force to effect regulation thereof, and means for varying and predetermining the force so applied including a ring non-rotatable with the hub and movable axially thereof, adjustable non-rotatin control means for effecting the axial shifting of said ring, a lever rotatable with said hub and having operative engagement with said ring for pivotal movement in response to the shifting thereof, and means actuated by said lever for varying the effective application of said force to said regulator valve in response to adjustment of said control means.

18. A propeller adjusting mechanism of the character described for use with an hydraulically adjustable propeller having provision within its hub for adjusting the pitch of its blades upon the application of fluid pressure thereto within arange of positive pitch positions and into a posiunobstructed, a cover plate fltting said annular memberand forming therewith a sealed self-contained reservoir rotatable with the propeller shaft for receiving a quantity of operating fluid, pump and valve chambers carried on said annular member within said reservoir, pump and valve means in said chambers in communication with said reservoir, means for positively driving said pump means to cause the developing of a source of fluid pressure, a regulator valve member also within said reservoir and responsive to the speed of rotation thereof for controlling the application of said pressure source, and curved fluid pressure conduits on said annular member conforming generally with the shape thereof and located outwardly of the propeller shaft for conducting the fluid from said pump means to said regulator valve and from said valve as controlled ghereby for selective application to the propeller 20. A propeller control mechanism of the character described for use with an hydraulically adjustable propeller having a hub and a plurality of blade sockets and fluid actuated means for effecting adjustment of the pitch of the blades in each of the blade sockets comprising an annular housing adapted to be received over the propeller shaft adjacent said hub leaving said shaft clear and unobstructed and containing a quantity of operating fluid, pump means within said housing, means for positively driving said pump means upon rotation of the propeller to provide a source of operating fluid under pressure, said pump means being normally immersed within said fluid in the reservoir during operation, a pair of fluid pressure conduits communicating with said reservoir for supplying directed fluid pressure to the propeller hub, a' regulator valve within said reservoir responsive to the speed of rotation of said propeller for selectively controlling the application of said pressure fluid to one or the other of said conduits, said conduits being curved to conform generally with said housing, and each of said conduits having, discharge openings formed therein in corresponding radial and angular locations in relation to each of the plurality tion of negative pitch, comprising a self-contained unit rotatable with the propeller and including a source of fluid pressure, a regulator valve movable outwardly of said hub for controlling the application of said fluid pressure to said propeller hub in response to the speed of rotation thereof, means for applying a substantially uniform predetermined force for opposing the outward movement of said regulator valve and balancing the effect of centrifugal force thereon at a predetermined speed of rotation, control means for varying the effective application of said opposing force to cause the balancing of forces to occur at different predetermined speeds within said range of positive pitch positions, said control means also being operable to a negative pitch position, and means effective in said latter position for retaining the regulator member in its innermost position and restraining regulating movement thereof under the action of prising an annular member adapted to be re-.

ceived over the propeller shaft adjacent the propeller hub leaving said shaft entirely clear and of blade sockets for supplying fluid concurrently to each of said sockets from one or the other of said conduits for effecting operation of the fluid actuated means therein.

21. A self-contained propeller control mechanism of the character described for an hydraulically adjustable blade propeller comprising a hub, a blade rotatably mounted in said hub,

blade adjusting means operable upon application of fluid pressure thereto for effecting adjustment of the pitch angle of said blade, a housing rotatable with said hub and forming a sealed reservoir for containing a quantity of operating fluid, means supported from outside said rotating housing and secured against rotation therewith and having a pump actuating portion extending into said housing, pump means rotatable with said housing and having operative engagement with said actuating portion for positive actuation thereof during rotation of said propeller to develop from said sealed reservoir a source of fluid pressure, a regulator valve member within said housing and directly movable under a force varying with the speed of rotation of said propeller for controlling the application of said fluid pressure to said blade adjusting means, means for opposing the movement of said regulator valve member with a predetermined force to effect regulation of the position thereof and of the setting of said propeller blade to a predetermined value, and means continuously operable from outside said rotating hub during rotation of said propeller for effecting variation in the force of said opposing means to cause corresponding regulation of said propeller to a desired speed condition.

22. A propeller control mechanism as defined in claim 21 in which the means for eflecting variation in the force of the opposing means comprises a control operable from outside said rotating hub and adjustable over a range of flight positions and into a feathered position, means operated by said adjustable control and cooperating with said opposing means for changing the eflective force applied to said regu-- lator valve in the several flight positions of said control. and means effective in the feathered position of said control for reversing the sense of the opposing force to assure the maintenance of said blade in its feathered position.

23. A control mechanism for a hydraulically adjustable propeller of the character described which comprises a hub, a blade rotatably mounted in said hub, blade adjusting means operable upon application of fluid pressure thereto for effecting adjustment of the pitch angle of the blade, means supported from outside said rotating housing and secured against rotation therewith and having a pump actuating portion extending into said housing, pump means rotatable with said housing and having operative engagement with said actuating portion for positive actuation thereof during rotation of said propeller to develop from said sealed reservoir 9, source of fluid pressure, a regulator valve member within said housing and movable for controlling the application of said source of fluid pressure to said blade adjusting means, conduits controlled by said regulator valve for supplying said fluid pressure to said blade adjusting means and for discharging the fluid therefrom back into said sealed reservoir, means within said housing for effecting adjustment in the position of said regulator valve to cause change in the pitch angle of the blades, and control means connected to said adjusting means and secured against rotation with said housing for controlling said adjusting means to predetermine'the pitch of said blades, said control means being continuously operable during rotation of said pr'opeller.

24. A propeller control mechanism of the character described for use with a propeller having a plurality of adjustable blades comprising a sealed housing rotatable with said propeller and adapted to contain a quantity of operating fluid, pump means within said housing for subjecting said fluid to pressure, a regulator valve member within said housing and responsive to the speed of rotation of said propeller for controlling the member through some of said fluid passages with discharge of fluid from the others of said passages back to said reservoir.

25. A propeller control mechanism of the character described for use with an hydraulically adjustable propeller having provision for eiiecting adjustment of pitch of the propeller blades upon the application of fluid pressure thereto comprising a propeller hub, a housing rotatable with said hub and forming a self-contained reservoir for a quantity of operating fluid, pump means within said housing and communicating with said reservoir for developing therein a source of fluid pressure, pump actuating means having a part supported against rotation from' outside said housing and a part extending into said housing providing a positive drive for said pump means, a regulator valve member in said housing for controlling the application of said fluid pressure, said regulator valve member being responsive to the speed of rotation of said propeller and being in equilibrium at a predetermined speed of the] propeller, means for changing the equilibrium speed of said regulator valve member to efl'ect adjustment in the predetermined speed of the propeller, an external control non-rotatable with said propeller and settable through a predetermined range of positions each of which corresponds to a desired speed of the propeller, and means interconnecting said external control with said means for changing the equilibrium speed to provide for predetermining the speed of said propeller.

26. A propeller as defined in claim 24 in which I the regulator valve member is normally immersed in the body of fluid contained in said reservoir.

27. A propeller control mechanism of the character described for use with a propeller having a plurality of adjustable blades comprising a propeller hub adapted to be received on the propeller shaft, fluid pressure actuated means posi-' tioned within said hub radially outwardly of the propeller shaft, means for connecting said pressure actuated means with said blades to eflect pitch adjustments thereof in response to application of fluid pressure thereto, a housing rotatable with said propeller hub and forming a selfcontained sealed reservoir for receiving a quantity of operating fluid, said housing being located outwardly of the propel er shaft leaving said shaft clear and unobstructed, pump means rotatable with said hub and located radially outwardly of the propeller shaft, means supported from a non-rotating element forming a positive mechanical drive for said pump means to provide for subjecting said fluid to pressure upon rotation of said propeller, regulator means carried by said hub and located outwardly of said propeller shaft, said regulator means being rotatable with said hub and responsive to the speed of rotation of said propeller for controlling the application of said pressure fluid to said pressure actuated means to effect regulation of the pitch of the propeller blades to maintain a predetermined speed, an external control member for changing the speed at which said regulator means responds, and means interconnecting said external control with said regulator means.

28. A propeller control mechanism for an hydraulically adjustable constant speed propeller of the character described which comprises a housing rotatable with the propeller shaft, a reservoir in said housing for receiving a quantity of pressure actuating fluid, pump means within said housing communicating with said reservoir and operable upon rotation of said propeller for establishing a supply of fluid under pressure, a regulator valve member within said housing and movable in a substantially radial direction for selectively controlling said supply of pressure fluid in response to increase or decrease of the speed of rotation of said hub with respect to a predetermined desired value, said regulator valve member being itself directly responsive to centrlfugal force, said valve member displacing the fluid in said reservoir and having a resulting fluid pressure force effective thereupon, resilient means within said housing for opposing the centrifugal force effective upon said valve member with a substantially constant force whereby said valve is in equilibrium at a predetermined speed, and non-rotating means located exteriorly of said hub and interconnected with said resilient means for altering the force with which said valve is opposed to balance the centrifugal force thereof at a different predetermined speed, said valve body reaching equilibrium upon depletion of said quantity of fluid and resulting reduction in the opposing force thereof at a slower speed than said predetermined speed thereby indicating loss of fluid from said reservoir.

29. A propeller control mechanism of the character described for use with an hydraulically adjustable propeller having provision for efiecting adjustment of pitch of the propeller blades upon the application of fluid pressure thereto comprising a propeller hub, a housing rotatable with said hub and forming a self-contained reservoir tor a quantity or operating fluid, pump means within said housing and communicating with said reservoir for developing therein a source or fluid pressure, pump actuating means having a part supported against rotation from outside said housing and a part extending into said housing providing a positive drive for said pump means, --a regulator valve member in the fluid in said housing for controlling the application of said fluid pressure, said regulator valve member being responsive to the speed of rotation of said propeller and being opposed by the fluid pressure of the fluid which it displaces, said valve member being in equilibrium at a predetermined speed of the propeller, means for changing the equilibrium speed of said regulator valve member to effect adjustment in the predetermined speed of the propeller, an external control non-rotatable with said propeller and settable through a predetermined range or positions each or which corresponds to a desired speed of the propeller, and means interconnecting said external control with said means for changing the equilibrium speed to provide for P predetermining the speed of said propeller, de-

pletion of the quantity or operating fluid effecting reduction in the fluid pressure opposing said valve so that equilibrium is manifest at a propeller speed less than said predetermined setting.

WERNER J. BLANCHARD. CHARLES S. J. MscNEIL. 

